Gray Matters: The Minnesota Zoo's Dolphin Problem

Everyone loves the dolphins at the Minnesota Zoo. When one of them dies unexpectedly, especially a young pup, it raises uncomfortable questions about both the dolphins and those of us who love them.

Dolphin at Minnesota Zoo
Cameron Wittig
The zoo is asking for $8 million from the state to renovate the Discovery Bay dolphin exhibit.

The necropsy connects Taijah’s rapid downward spiral to two precipitating details: a broken tooth that remained from a broken jaw she incurred a few months earlier (“We believe it was from an encounter with Allie,” Willis says) and a traumatic acoustic event that Willis did not mention. “On Thursday, February 2,” the report states, “the dolphin [Taijah] was observed to be squinting her right eye. Fire-alarm testing occurred in the building causing nervous behavior to be displayed by the dolphin and her mother.”

While Willis attributes most dolphin ulcers to acid and bacteria, he admits that stress may be a factor, but like Wunschmann in the necropsy, he leaves the relationship inconclusive. “It’s a contributing factor, but it’s not a causative factor necessarily,” he says. But Willis clearly understands that there is a connection. In a later conversation about future plans for Discovery Bay, he laments the state of the concrete seats in the dolphin arena, and says workers had to suspend drilling wooden benches in the amphitheater because the drilling was causing the dolphins obvious stress. But he also points out that it’s his understanding that the ambient acoustic level in the ocean is higher than in an aquarium’s pool. As with his statistical analysis of their longevity in captivity vs. in the wild, his underlying point is obvious: Dolphins are better off under our care.


Zoos have always been a place where our sense of wilderness uncomfortably runs up against our understanding of the limits on our own civilization. Think of the 19th-century poet Rainer Maria Rilke and his captive panther; by the end of the second stanza, it’s unclear whether he’s writing about the panther or himself:

His vision, from the constantly passing bars,
has grown so weary that it cannot hold
anything else. It seems to him there are
a thousand bars; and behind the bars, no world.

As he paces in cramped circles, over and over,
the movement of his powerful soft strides
is like a ritual dance around a center
in which a mighty will stands paralyzed.

Perhaps it’s inevitable that as our understanding of the animals we keep in cages becomes more and more sophisticated, especially animals with brains of a similar size and function to our own—found in such large mammals as elephants, great apes, and dolphins—our feelings about keeping them in cages become more conflicted. In 2000, dolphin and whale neurologist Lori Marino published what is regarded as a groundbreaking mirror study, in which she demonstrated self-awareness in bottlenose dolphins. Repurposing an experiment that had previously been used with chimpanzees, Marino marked X’s on the dolphins’ sides and faces, in locations beyond their peripheral vision, and placed a mirror in their tank at the New York Aquarium. The dolphins went to the mirror to examine the markings. Prior to Marino’s research, self-recognition only had been observed in higher primates.

“You can throw stuff down there, give them Hula-Hoops and balls to play with and call that enrichment, but really it’s nothing. They get bored really easily. Because what’s enriching for them are their social groups.”
—Lori Marino, dolphin and whale neurologist

Since Marino’s study, scientists have observed dolphins using tools (using sponges to protect their snouts as they fish off the coast of Australia), having a dolphin “culture” (passing down skills between generations), and even using language (orcas, the largest member of the dolphin family, have different clicking dialects). All of these characteristics emphasize the species’ social ability. With a range spanning thousands of miles in the open ocean, dolphins in the wild freely associate among vast social groups, sometimes in numbers that would be the envy of the most popular Facebook users.

Since her study, Marino has gone through a sort of moral awakening, coming to the conclusion that dolphins are too socially sophisticated to live in zoos and aquariums. “We’re talking about animals that are so intelligent, and so socially complex, the idea of ‘environmental enrichment’ for them in captivity is really tough,” she says. “You can throw stuff down there, give them Hula-Hoops and balls to play with and call that enrichment, but really it’s nothing. They get bored really easily. Because what’s enriching for them are their social groups. And they can never have that in captivity.”

If dolphins can be bored, if they can bully other dolphins, if they can feel enough anxiety to cause themselves ulcers, should we perhaps rethink how appropriate it is to keep them at the zoo? As I reported this story, I began to wonder if I was experiencing a similar awakening. I’m not an animal rights activist—I eat meat and I grew up going to zoos.

My dad’s best friend was the director of the aquatic building at Como Zoo for 30 years before becoming a consultant for places such as the Great Lakes Aquarium and Sea Life Aquarium at the Mall of America. Denny was a truck driver who got a job with the city as a zookeeper, and when I was a kid he would take us backstage to feed the orangutans yogurt and to race between the tiger cages as the big cats loped along, tracking the delicious little kid racing next to them in his baseball jersey. Denny was around to see the industry become much more sophisticated, with more and more PhDs and master’s degrees coming on board to take his place. He witnessed zoos and aquariums become less and less about entertainment and more and more about education and science. “Education is important, but I have to be honest with you,” he says, “zoos have always been just as much about entertainment.”

Although Willis is clearly somebody with a great amount of affection for and knowledge about animals, he’s also a frustrated showman. Since the problems in 2006, the zoo has been forced to scale back its dolphin shows, referring to them as “dolphin training presentations.” The animals he’s left with are older and less athletic, and he says his training staff is frustrated that it has been unable to show off what these animals can really do.

As best it can, the zoo tries to mirror the way dolphins operate in the wild—in their dotage or not, Willis refers to his dolphins as “ambassadors for their species.” But the zoo’s main strategy for maintaining the dolphins’ social verisimilitude with the natural world seems to be to plan for small groups of female dolphins alongside lone males. “Young males get kicked out of the family group so they won’t breed with their mothers and sisters,” Willis says. “That’s how we manage dolphins [in the aquarium], too.”

So he’s looking forward to the upcoming Discovery Bay renovations and the opportunity to swap out Semo for some younger females, allowing the zoo to establish a new “matra-line,” a group of dolphins established around a line of related females. But he also appreciates this opportunity for changeover as a teachable moment. Before I leave, he tries one more pop quiz on me. “Do you know what percentage of our animals die?”

“I’m not sure,” I respond.

“All of them,” he says.

He got me.

“We teach you that animals are cool,” he says. “It’s great if you love our dolphins, if you come here because you like to see Ayla, the dolphin who isn’t straight, because she’s a fighter. But she’s going to die. And your mother is going to die. And you’re going to die. And that’s hard for little kids. It’s hard for everyone. I have a 14-year-old beagle, and it’s hard for me. But it’s part of life. And so when we say we’ve had six dolphins die in six years, I can say, ‘Yes, and all of them will die someday.’ ” He raises his eyebrows at me. “So the question isn’t, ‘Is that too many deaths?’ The question is, ‘Are you responsibly caring for those animals?’ ”